The invention relates generally to hammerbreakers and is particularly concerned with protective shields for the rotor of such hammerbreakers. The hammerbreaker rotor in connection with which the invention is described comprises a plurality of discs which are mounted on a shaft, with hammers being pivotably or rockably mounted between the discs on rods arranged eccentrically relative to the rotor shaft and which extend through the discs.
Hammerbreakers are conventionally used for the comminution or breaking-up of metallic or non-metallic materials or mixtures of metallic and non-metallic materials. Customarily hammerbreakers comprise a stationary casing or housing in which a rotor is rotatably mounted. Fixed to the inner side of the housing are one or more stationary impact blocks or anvils which cooperate with the hammers mounted on the rotor. The rotor is usually driven at high speed and has a plurality of rods or shafts spaced radially from and extending parallel to the rotor shaft. The hammers are freely pivotably mounted on these rods or shafts, and comminution or breakup of the material is effected by the coaction between the rotor hammers and the stationary anvil which is usually situated at the inlet for the material to the housing.
The rotor hammers are distributed around the periphery thereof in spaced relationship circumferentially and axially of the rotor. The rotor body consists of a plurality of discs rigidly connected with the rotor shaft. If the material to be comminuted consists entirely or partially of metal, the outer surfaces of the discs which collectively form the rotor body and between which the rotor hammers are pivotally mounted will be subjected to considerable wear and will thus become damaged by the impinging material. After a relatively short operating time, significant amounts of metal will be torn or ground from the circumference of the discs and the discs become no longer usable and must be replaced. In this connection it should be appreciated that from a practical viewpoint it is more economical if only the rotor hammers need to be produced from especially hard and high-quality material with steel of lesser quality being adaptable for use in other parts. This applies to the discs which form the rotor body and it thus would be particularly advantageous if the danger of wear or damage to the circumference of the discs could be significantly reduced or eliminated.
Accordingly, it is the aim of the present invention to provide protection for the edges of the discs in a hammerbreaker rotor of the kind comprising a series of discs mounted coaxially on a driving shaft and a number of hammers freely pivotally mounted between the discs on pivot shafts spaced radially from and extending parallel to the axis of rotation of the rotor.